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Observations of angina and myocardial infarction in constrictive pericarditis.

The common symptoms of constrictive pericarditis, i.e. dyspnea on exertion, shortness of breath and cough, relate to impairment of ventricular filling and to a progressive rise in systemic and pulmonary venous pressures. Myocardial ischemia, angina and myocardial infarction are rarely associated with this disease. We have encountered two patients with constrictive pericarditis, one presenting with angina and the other with acute anterior wall infarction. Possible etiologies of constrictive pericarditis in the first case include cardiac surgery, chronic renal failure and myocarditis; in the second case, Crohn's disease. The proposed mechanism of chest pain in the first patient was a reduced cardiac output resulting in underperfusion of the coronary arteries, although it is possible that the patient experienced angina due to the presence of severe coronary artery disease. In the second patient an anterior wall infarction and post-infarction angina were attributed to obliteration of the left anterior descending artery by constraint of a thickened pericardium. In both cases non-invasive imaging modalities were not of use in establishing the diagnosis of constrictive pericarditis. Clinical awareness and accurate hemodynamic measurements continue to play a key role in the diagnostic process.

Angina Pectoris↗

Results of subtotal pericardiectomy for constrictive pericarditis.

The operative approach to constrictive pericarditis still remains a surgical challenge. Subtotal pericardiectomy through median sternotomy was analyzed retrospectively in a series of 84 patients operated on for chronic constrictive pericarditis at our institution between 1979 and 1989. The mean duration of symptoms prior to diagnosis was 20 +/- 6 months (1-264 months). Preoperatively, 72% of patients were in NYHA class III or IV, presented signs of right cardiac failure (88%) or anasarca (18%). Chest X-ray showed pericardial calcifications in 40% of the patients. Echocardiography revealed pericardial thickening in 62%. Among 62 patients in whom cardiac catheterization was performed, a characteristic dip-and-plateau was found in 47 patients (76%). A specific etiologic factor was identified in only 37 patients: tuberculosis (12%), recurrent acute pericarditis (9%), hemopericardium (9%), radiotherapy (5%), previous cardiac surgery (4%), bacterial infection (2%), myocardial infarction (2%) and connective tissue disease (2%). In 47 patients (55%), the constrictive pericarditis remained idiopathic. In seven patients we performed a redo-operation for previous incomplete pericardiectomy. Subtotal pericardiectomy (from phrenic nerve to phrenic nerve) was performed in 75 patients. A palliative procedure consisting of pericardial "meshing" was performed in nine patients due to an unsatisfactory cleavage plane. Cardiopulmonary bypass was used in four patients for coexistent cardiac lesions. The operative mortality was 2.3% (two patients: septicemia and pulmonary embolism). Seven patients (8.2%) developed early on-lethal complications. The probability of survival for patients discharged for the hospital was 94% at 3 years and 87% at 7 years. There were four late deaths and no reoperation for recurrent constriction.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiopulmonary Bypass↗

Traumatic hemopericardium and chronic constrictive pericarditis.

Chronic constrictive pericarditis following traumatic hemopericardium has been reported in recent years, but it has not been reproduced experimentally in dogs. The present study attempted to produce posttraumatic constrictive pericarditis in 34 experimental animals. Hemopericardium by means of trauma to the epicardium or pericardium was produced by a sharp instrument or by the injection of autologous blood inside the pericardial sac. All animals were killed at intervals between 3 and 31 months. The animals in which hemopericardium was induced by injecting blood into the pericardial cavity showed no changes. The hemopericardium was completely resolved without noticeable residual trace. Animals having hemopericardium as a result of trauma evidenced a well-developed constrictive pericarditis that was documented clinically, hemodynamically, and histologically. These experimental findings indicate that chronic constrictive pericarditis may well be due to traumatic hemopericardium rather than to specific infection.

Animals↗

Correlation of intra-arterial contrast stasis with flow patterns at constrictions, branches and bends: an experimental model.

Flow patterns at bends and branches have been studied in an easily constructed open channel model so as to determine whether zones of stasis and poor mixing at constrictions, bends and branches can be correlated with certain arteriographic appearances. At bends, spiral flow lines and static zones occur which resemble those seen occasionally in the aortic arch and carotid siphon. At branches, stasis occurs on the outer walls of the branch mouths both in the experiments and arteriography, and constrictions easily produce downstream stasis, previously demonstrated in both arteries and open-channel experiments. Upstream stasis, not previously recorded, can also occur in arteries and model associated with severe constrictions. Occasionally stasis may extend along the whole length of one wall of a vessel when there is a downstream constriction, resembling arteriographic appearances seen in the internal carotid artery in patients with raised intracranial pressure, in those undergoin hyperventilation and also in coronary and other arteries. Despite known rheological differences between blood and water, the experimental findings are thought to be meaningful, and to indicate that there are within arteries, areas where turbulent mixing forces are weak or absent, resulting in arterial stasis.

Angiography↗

Long-term results with vacuum constriction device.

From November 1985 to April 1990, 216 consecutive patients were treated with the vacuum constriction device. Patients were mailed an initial questionnaire (group 1) and a long-term questionnaire (group 2) at a median followup of 3 and 29 months, respectively. Of 202 available patients 161 in group 1 (75%) and 115 in group 2 (57%) responded. Regular use of the vacuum constriction device was reported by 69% group 1 and 70% group 2 patients. patient and partner satisfaction was 82% and 87% in group 1, and 84% and 89% in group 2, respectively. There were no significant differences between the groups with respect to regular use and patient or partner satisfaction (p < 0.05). Quality of erection was evaluated for hardness, length and circumference, and with satisfaction greater than 90% in both groups. Median times per month of successful intercourse were 1, 4 and 4 for the year before, during and after obtaining the vacuum constriction device in group 2. Also, 79% of the patients in group 2 reported a statistically significant increase in the frequency of intercourse per month in the first year, which was sustained beyond the first year in 77% (p < 0.01). Our results support the efficacy of the vacuum constriction device for the treatment of impotence. Overall regular use rates as well as patient and partner satisfaction appear to be high. Furthermore, excellent initial results appear durable in most patients.

Adult↗

Constrictive pericarditis: assessment of current diagnostic procedures.

Constrictive pericarditis frequently poses a diagnostic challenge because of its varied manifestations. Accurate diagnosis is essential, however, because surgical decortication may yield excellent clinical results. Although new diagnostic procedures have helped the clinician to diagnose constrictive pericarditis, the initial clinical suspicion of this diagnosis must be high for appropriate interpretation of these tests. Echocardiography is useful, primarily for distinguishing various other cardiac abnormalities that may simulate constrictive pericarditis. Computed tomography is a valuable procedure for assessment of pericardial thickening. In addition, evaluation of early diastolic filling by computerized digitization in conjunction with echocardiography, angiography, and invasive hemodynamics shows promise as a diagnostic tool. Even with these new diagnostic aids, distinguishing constrictive pericarditis from restrictive cardiomyopathy may be difficult and, in some cases, may necessitate an exploratory operative procedure.

Aged↗

Management of iatrogenic vaginal constriction.

OBJECTIVE: To prospectively assess the outcomes of four approaches to the surgical management of iatrogenic vaginal constriction. METHODS: A prospective study was initiated to evaluate all women who presented to our practice with the complaint of apareunia or dyspareunia secondary to postoperative vaginal constriction. All participants were initially offered and failed a trial of manual dilation. Between 1997 and 2002, 20 women underwent one of four surgical procedures: Z-plasty, vaginal incision of constriction ring, vaginal advancement, or placement of free skin graft. All 20 participants have been followed postoperatively, including assessment of dyspareunia and postoperative vaginal length and caliber. RESULTS: Three patients underwent Z-plasty, eight had incision of vaginal ring or ridge, eight had vaginal advancement, and one underwent placement of a free skin graft. Mean follow-up was 17 months (range, 3-32 months). Subjective cure was defined as resumption of pain-free vaginal intercourse. Objective cure was defined by findings on physical examination. The overall subjective and objective cure rates were 75% and 85%, respectively. CONCLUSION: The appropriate surgical procedure depends on the site and extent of the vaginal constriction, the state of the surrounding tissue, and the overall length and caliber of the vagina.

Adult↗

Septal bounce, vena cava plethora, and pericardial adhesion: informative two-dimensional echocardiographic signs in the diagnosis of pericardial constriction.

To assess the diagnostic value of three different two-dimensional echocardiographic signs of pericardial constriction (early diastolic septal bounce, plethora of the inferior vena cava with blunted respiratory response, and pericardial adhesion), two independent observers retrospectively evaluated echocardiograms in 100 patients, 39 of whom had pericardial constriction, 15 had hemodynamically insignificant pericardial thickening, 16 had restrictive cardiomyopathy, and 30 had normal hearts. Causes of pericardial disease included cardiac surgery, malignancy, and uremia. Sensitivity and specificity of the three signs for constriction were 62% and 93% for septal bounce, 79% and 80% for vena cava plethora, and 79% and 90% for pericardial adhesion, respectively. The presence of either vena cava plethora or pericardial adhesion increased sensitivity, whereas the presence of both plethora and adhesion increased specificity. Between the two readers, septal bounce was the most consistent and pericardial adhesion the least consistent sign. False positive results included right ventricular pacing or left bundle branch block (septal bounce), postpericardiotomy (pericardial adhesion), and right heart failure (vena cava plethora). False negative results were often caused by technical problems with imaging. We conclude that these three two-dimensional echocardiographic signs are useful in differentiating pericardial constriction from hemodynamically insignificant pericardial thickening or restrictive cardiomyopathy.

Aged↗

Constrictive chronic pericarditis in children.

Constrictive pericarditis is a uncommom disease in children. We have now encountered pericardial thickening as the cause of severe constrictive physiology in two patients, one also having haemodynamic features of restrictive cardiomyopathy. Both patients, who had refractory ascites and evidence of increased systemic venous pressure, underwent Doppler echocardiography, cardiac catheterisation, and magnetic resonance imaging. Resonance imaging failed to show any thickning of the pericardium, but cardiac catheterisation revealed diastolic equalisation of pressures in all four chambers, with only mild elevation of pulmonary pressure in the first patient, but nearly equalisation of diastolic pressure, and a very high pulmonary arterial pressure with a difference of 7 mm Hg between the end diastolic pressures in the two ventricles in the second patient. Doppler revealed a restrictive pattern of mitral inflow, with high E and small A velocities and a short deceleration time. The clinical background did not suggest pericardial disease in either of the patients. We conclude that a careful search is needed to uncover constrictive pericarditis when there is no previous disease which may suggest late pericardial constriction. The haemodynamic features of restrictive cardiomyopathy can co-exist with pericardial restriction, and differentiation between the two entities is critical in view of the diverse management and prognosis of the two conditions.

Child↗

Sauropus androgynus-constrictive obliterative bronchitis/bronchiolitis--histopathological study of pneumonectomy and biopsy specimens with emphasis on the inflammatory process and disease progression.

AIMS: The histopathology of the Sauropus androgynus (SA)-constrictive bronchiolitis obliterans (BO) is still controversial. A recent report using pneumonectomy specimens showed that the major histopathology was obliterative arteriopathy with segmental necrosis of small bronchi instead of constrictive BO as previously described. METHODS AND RESULTS: We analysed semiquantitatively and immunohistochemically the histopathology of one pneumonectomy and four biopsies specimens of SA-associated lung disease. We found a significant number of constrictive and obliterative bronchioles 1 mm or less in diameter and segmental inflammatory destruction with complete luminal obliteration of the bronchi less than 3 mm in diameter in the pneumonectomy specimen (37% and 25%, respectively). Fibromuscular intimal sclerosis of the bronchial arteries was identified in 15% of the bronchi 4 mm or less in diameter. The inflammation in these airways was composed predominantly of T-lymphocytes, macrophages, mast cells and eosinophils. They were present throughout the evolutionary stages of the bronchiolitis ranging from early oedematous to the late fibrotic obliterative stage. Double immunohistochemical stains revealed negative proliferative cell nuclear antigen for most of the T-lymphocytes and macrophages but positive for fibroblasts. CONCLUSIONS: A more accurate histopathological designation of the SA-associated lung disease should be constrictive obliterative bronchitis/bronchiolitis, with the participation of T-lymphocytes, macrophages, mast cells, eosinophils and fibroblasts in its morphogenesis. The persistent accumulation of inflammatory cells was mediated predominantly by continued recruitment to the site of injury from the bloodstream, resulting eventually in the irreversible fibrosis of the bronchioles and the bronchi less than 3 mm in diameter. Obliterative arteriopathy is suspected of being only an indirect contributing factor.

Bronchi↗

Nontraumatic paralysis of the radial nerve with multiple constrictions.

PURPOSE: To present an uncommon lesion of radial nerve paralysis with multiple constrictions. METHOD: Eight patients were treated in our department between January 1994 and August 2000. There were 4 men and 4 women with a mean age of 26 years (10-43 y). The radial nerves of all patients were explored. There were 1 to 5 segmental constrictive lesions at the main trunks of the radial nerves or the posterior interosseous nerves; no obvious extrinsic compression was noted. Epineurolysis was performed in 3 patients, in the other 5 patients the constricted portions of the nerves were resected, and neurorrhaphy was performed in 2 patients, nerve-grafting in 3. Histologic examination of the resected portions showed concentration of inflammatory cells around the vessels in the perineurium. RESULTS: The patients were followed-up for 6 months to 4 years after surgery. Seven patients had at least grade 4 muscle strength in the involved muscles. One patient who was treated by external neurolysis 15 months after onset had no signs of recovery 10 months after surgery. CONCLUSIONS: Nontraumatic paralysis of the radial nerve with multiple constrictions is very uncommon. The etiology may be a focal inflammatory response around the feeding arteries in the perineurium.

Adolescent↗

Hypoperfusion of the myocardium relative to myocardial metabolism during delayed coronary constriction.

OBJECTIVE: The aim was to test the hypothesis that the myocardium becomes hypoperfused, relative to its metabolic demands, during the delayed coronary constriction which is observed following termination of a period of sympathetic stimulation. METHODS: This was tested by beat by beat analysis of the ratio of coronary blood flow to the product of heart rate and systolic blood pressure (HR x SBP), an index of myocardial metabolism, in acutely instrumented open chest canine preparations, before, during, and after direct electrical stimulation of the left stellate ganglion. RESULTS: Myocardial metabolism increased in response to stellate stimulation, as evidenced by increases in heart rate, aortic blood pressure, and HR x SBP. These were accompanied by increased blood flow and decreased vascular resistance in the left anterior descending coronary artery. Delayed coronary constriction, defined as the period with the lowest coronary blood flow observed after the end of the stimulation, occurred 1 to 3 min after stimulation was terminated and was characterised by recovery of heart rate, blood pressure, HR x SBP, and coronary blood flow toward control levels, while coronary vascular resistance overshot to above control levels. The ratio of coronary blood flow to HR x SBP fell progressively in the poststimulation period to significantly less (mean 0.715, range of +/- 1 SEM 0.638 to 0.800, p < 0.05) than control (1.0, by definition) in experiments performed with partial prestenosis of the left anterior descending coronary artery. In a selected subgroup of observations with a mean reduction in coronary blood flow during delayed coronary constriction comparable to that reported previously, the flow/metabolism ratio was even lower (mean 0.239, range of +/- 1 SEM 0.202 to 0.284). CONCLUSIONS: The phenomenon of delayed coronary constriction clearly involves a mismatch between myocardial supply and demand: coronary blood flow becomes inappropriately low for the prevailing level of myocardial metabolism.

Animals↗

Clinical relevance of Doppler pulmonary venous flow characteristics in constrictive pericarditis.

The purpose of this study was to determine the diagnostic value of Doppler pulmonary venous flow in constrictive pericarditis, as assessed by transoesophageal echocardiography. It has been demonstrated previously that increased respiratory variation in Doppler pulmonary venous, but not in transmitral flow velocities, can identify patients with constrictive pericarditis, when transoesophageal echocardiography is used. In the present study we compared a group of 10 patients with constrictive pericarditis and a control group of 15 normal subjects with respect to pulmonary venous and transmitral flow velocities and their respiratory variation. Peak velocities and velocity time integrals of the systolic, early diastolic and late diastolic reversed pulmonary venous flow waves were measured. Peak velocities and velocity time integrals of the early and late diastolic transmitral flow waves were also measured. Measurements were made irrespective of the respiratory cycle, at the onset of inspiration and at the onset of expiration. Values for inspiration and expiration were expressed as percent difference of those obtained irrespective of the respiratory cycle. Peak velocity and velocity time integral of the pulmonary venous systolic and diastolic waves were significantly lower than in normal subjects. Furthermore, the difference between peak velocities of the diastolic wave obtained at the onset of inspiration and obtained irrespective of the respiratory cycle was significantly larger in constrictive pericarditis than in the control group (-20% vs -9%, P < 0.05). This also applied to the difference between velocity time integrals of the diastolic wave obtained at the onset of inspiration and obtained irrespective of the respiratory cycle (-22% vs -12%, P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Spinal expansion of saphenous afferents after sciatic nerve constriction in rats.

In rats with chronic constriction of one sciatic nerve, neurone pair responses to saphenous electrical stimulation were simultaneously recorded in sciatic (L5-6) and in saphenous (L2) spinal areas. In 16 rats with thermal hyperalgesia, 43 pairs of neurons were recorded, 4 and 14 days after constriction, on both sides of the spinal cord. On the side ipsilateral to nerve constriction, stimulation of the saphenous evoked excitatory responses in 90% of neurones recorded in the L5-L6 sciatic area, regardless of the post-constriction time. No responses were evoked by saphenous stimulation of the L5-L6 contralateral spinal cord neurones. The possibility that pre-existing connections are unmasked after nerve injury and impinge on sensitized neurones, contributing to abnormal pain sensations such as, for instance, extraterritorial pain, is discussed.

Animals↗

In-vitro assessment of the behavior of magnetic resonance angiography in the presence of constrictions.

RATIONALE AND OBJECTIVES: Time-of-flight magnetic resonance angiography (TOF/MRA) is increasingly used to assess the nature and severity of stenotic blood vessels. Flow artifacts associated with high flows and/or narrow constrictions may confuse the interpretation of these studies. Accurate TOF/MRA evaluations demand an understanding of the nature of these flow effects. METHODS: A two-dimensional TOF pulse sequence was used to acquire images of five smoothly constricted phantoms at various flows. Analysis included assessment of phantom appearance and quantification of apparent constriction diameter and signal variations. RESULTS: Most notable flow phenomena were a cone-shaped region of high signal, a region of signal void, and signal preservation along the wall. When visible, constriction diameter was accurately measured. CONCLUSIONS: The behavior observed in TOF/MRA images can be understood by considering the contributing mechanisms of phase dispersion, turbulence, poststenotic flow eddies, flow reversal, and flow separation.

Blood Vessels↗

Transperineurial vessel constriction in an edematous neuropathy.

The hypothesis that the accumulation of endoneurial edema can exert forces sufficient to occlude transperineurial vessels was tested using light microscopy and computer-assisted morphometry in rat sciatic nerve. Experimental nerves were exposed to a concentration of 10% procaine HCl, which from previous studies has been demonstrated to routinely produce an edematous neuropathy. For each vessel, a "constriction ratio" was defined by dividing its minimum intraperineurial lumen area by the average for minimum endoneurial and epineurial lumen cross-sectional areas. Constriction ratios were 0.91 +/- 0.26 (mean +/- SD) for control vessels and 0.28 +/- 0.25 for vessels in the procaine group (p less than 0.005). In addition, a strong negative correlation was observed between the morphologic demonstration of nerve edema and the transperineurial vessel constriction ratio (r = -0.85; p less than 0.002). It is concluded that in neuropathies characterized by widespread edema and increased endoneurial fluid pressures, the concomitant constriction of transperineurial vessels could diminish nerve blood flow and facilitate nerve injury.

Animals↗

Comparison of the effects of Bay K 8644 and aortic constriction on regional myocardial blood flow and function in canine nonischemic and ischemic myocardium.

The effects of Bay K 8644, aortic constriction, and a placebo on regional myocardial blood flows (RMBFs) and contractile function (RCF) were compared in three groups of open-chest anesthetized dogs during coronary stenosis. Bay K 8644 was investigated in two doses: 0.1 micrograms/kg, which exhibited no systemic hemodynamic effect, and 1 microgram/kg, which significantly increased arterial pressure. Aortic constriction was performed to raise afterload to the same extent as Bay K 8644 1 microgram/kg. As compared with placebo, Bay K 8644 0.1 microgram/kg, significantly increased coronary resistance, decreased RMBFs without changing RCF in nonischemic myocardial zones, and affected neither RMBFs nor RCF in ischemic zones. In nonischemic myocardium, Bay K 8644 1 microgram/kg increased RMBFs without affecting RCF, whereas aortic constriction did not modify RMBFs but decreased RCF. In ischemic myocardium, both Bay K 8644 1 microgram/kg and aortic constriction increased RMBFs but did not affect RCF. Thus, the low dose of Bay K 8644 exerts a direct and selective coronary vasoconstrictor effect that has no deleterious consequences on nonischemic RCF. Despite this intrinsic coronary vasoconstrictor effect, the high dose of Bay K 8644 increases RMBFs and maintains RCF in both ischemic and nonischemic zones in relation with the drug-induced increases in coronary perfusion pressure (both zones) and in contractility (nonischemic zones).

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗

CT and MR evaluation of pericardial constriction: a new diagnostic and therapeutic concept.

Eighty patients with pericardial constriction confirmed by catheter data were studied by CT (n = 79), MR imaging (n = 24), or both. To determine the validity of these imaging methods for subsequent treatment, 30 patients' studies were evaluated retrospectively (1980-1984) and 50 (1985-1991) prospectively. Twenty patients from the first group and 30 patients from the second group underwent pericardiectomy. By systematic analysis of CT scans and MR images it was possible to characterize the morphology of pericardial constriction (n = 80); to identify global (n = 27), right-sided (n = 46), left-sided (n = 2), annular (n = 2), effusive (n = 2), and epicardial (n = 1) forms of pericardial constriction; and to define parameters of myocardial atrophy and fibrosis (n = 17). Seventeen patients had myocardial atrophy, fibrosis, or both. Seven of them underwent pericardiectomy; all died of acute myocardial failure (100%). Four (9.3%) of 43 patients without myocardial atrophy or fibrosis died as a consequence of other complications. The method of thoracotomy and periepicardiectomy was continuously adjusted to the preoperative CT and MR findings. Thus, the clinical use of CT and MR imaging in patients with known or suspected pericardial constriction is based on (a) exclusion of patients with restrictive hemodynamics from diagnostic thoracotomy, (b) preoperative determination of the method of thoracotomy and extent of pericardiectomy, and (c) exclusion of patients with myocardial atrophy or fibrosis from pericardiectomy.

Adult↗